Film scholars have long posed the question of the specificity of the film medium and the apparatus of cinema, asking what is unique to cinema, how it constrains and enables filmmakers and audiences in particular ways that other media do not. This question has rarely been considered in relation to scientific film, and here it is posed within the specific context of cell biology: What does the use of time-based media such as film coupled with the microscope allow scientists to experience that other visualization practices do not? Examining three episodes in the twentieth-century study of the cell, this article argues that the apparatus of microcinematography constitutes what might be thought of as a technical portal to another world, a door that determines the experience of the world that lies on the other side of it. In this case, the design of apparatuses to capture time-lapsed images enabled the acceleration of cellular time, bringing it into the realm of human perception and experience. Further, the experience of the cellular temporal world was part of a distinct kind of cell biology, one that was focused on behavior rather than structure, focused on the relation between cells, and between the cell and its milieu rather than on cell-intrinsic features such as chromosomes or organelles. As such, the instruments and technical design of the microcinematographic apparatus may be understood as a kind of materialized epistemology, the history of which can elucidate how cinema was and is used to produce scientific knowledge.